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A Phase I/II, Open-label Study to Investigate the Safety, Tolerability, PK, and Preliminary Efficacy of FB849

Registration Number
NCT05761223
Lead Sponsor
1ST Biotherapeutics, Inc.
Brief Summary

This is the first-in-human, multicenter, open-label Phase I/II study to investigate the safety, tolerability, pharmacokinetics (PK), pharmacodynamics, and preliminary efficacy of FB849 alone and in combination with pembrolizumab in subjects with advanced solid tumors for whom no standard therapy is available.

Detailed Description

The study will be conducted in 4 parts: Phase I dose-escalation and dose-expansion parts with FB849 monotherapy and Phase II dose-escalation and dose-expansion parts of FB849 in combination with pembrolizumab.

The Phase Ia dose-escalation part will use an adaptive study design termed Bayesian optimal interval (BOIN) design to investigate the safety and tolerability of FB849, and determine the maximum tolerated dose (MTD) and preliminary recommended Phase II dose (RP2D) of FB849. A BOIN design is a hybrid of rule-based and model-based design, which has the flexibility of dose escalation and de-escalation and allows more subjects to be enrolled into the doses closest to the target toxicity rate.

The Phase Ib dose expansion of FB849 monotherapy part will be initiated once the preliminary RP2D has been determined in the Phase Ia part to provide assessment of safety and anti-tumor activity of FB849 in subjects with advanced solid tumors. It will evaluate FB849 at the preliminary RP2D. Based on data from the Phase Ia part, an additional dose ≥ 1 dose lower than the preliminary RP2D may be evaluated if needed, as determined by the safety monitoring committee (SMC). Subjects will be enrolled using a Simon's two-stage enrollment. If more than 1 dose level cohort is evaluated, subjects will be randomized to a dose level. For each cohort, an interim analysis will be performed prior to opening the second stage of enrollment in each cohort (Simon's two-stage optimal design).

Phase IIa enrollment will be initiated after Stage 1 of Phase Ib is completed. The selected RP2D from the prior Phase Ib part and a dose level ≥ 1 dose lower than the RP2D of FB849 will be selected by the SMC and will be evaluated in combination with a standard dose of pembrolizumab. Dose escalation will follow a BOIN design, but with at least 6 subjects at each FB849 dose level.

In the Phase IIb part of the study, subjects with Type A cancer, Type B cancer, or Type C cancer will be enrolled in 3 cohorts to evaluate FB849 at the RP2D in combination with a standard dose of pembrolizumab to provide assessments of safety and anti-tumor activity of FB849. Enrollment will follow a Simon's two-stage design enrollment, similar to Phase Ib.

Subjects will be monitored for safety, tolerability, and preliminary efficacy throughout the study. Tumor response will be assessed by the investigator according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 approximately every 6 weeks (± 3 days) in the first 18 weeks, then every 12 weeks (± 7 days) thereafter until disease progression, using computed tomography or magnetic resonance imaging of the chest, abdomen/pelvis, and if clinically indicated additional assessments eg, craniocerebral imaging, bone scan. Treatment with FB849 will continue until the start of a new anti-cancer treatment, disease progression, subject refusal, unacceptable toxicity, death, lost to follow-up, etc, whichever occurs first. Subjects who discontinue treatment due to other reasons than disease progression will continue with tumor assessments as per protocol until disease progression, death, or starting a new anti-cancer treatment.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
151
Inclusion Criteria
  • Subject should understand, sign, and date the written ICF prior to screening.
  • Male or female aged 18 years or older.
  • Subjects must have at least 1 measurable target lesion according to RECIST version 1.1.
  • Eastern Cooperative Oncology Group (ECOG) performance status 0 or 1
  • Life expectancy ≥ 3 months in the opinion of the investigator.
  • Adequate organ function and bone marrow function as indicated by the following screening assessments performed within 14 days prior to the first dose of study treatment
Exclusion Criteria
  • Known allergy or hypersensitivity to any component of the study treatment.
  • Has a known additional malignancy that is progressing or has required active treatment.
  • Has abnormal or inadequately controlled endocrine function.
  • Inability to take oral medication or significant nausea and vomiting, malabsorption, external biliary shunt, or significant bowel resection that would preclude adequate absorption of oral medication.
  • Previous anti-cancer therapy, including chemotherapy (chemotherapy with nitrosourea or mitomycin should be at least 6 weeks prior to initiation of study treatment), radiotherapy, molecular targeted therapy, or other investigational drugs received ≤ 4 weeks; endocrine therapy ≤ 2 weeks or ≤ 5-half-lives (whichever is shorter) prior to initiation of study treatment.

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Phase IIb dose-expansion part of FB849 in Combination with Pembrolizumab (Type C cancer)Phase IIb dose-expansion part of FB849 in Combination with Pembrolizumab (Type C cancer)Participations will receive FB849 orally once a day in combination with pembrolizumab.
Phase IIa dose-escalation part of FB849 in Combination with PembrolizumabPhase IIb dose-escalation part of FB849 in Combination with PembrolizumabParticipations will receive FB849 orally once a day in combination with pembrolizumab.
Phase Ib dose-expansion of FB849 monotherapyPhase Ib dose-expansion of FB849 monotherapyParticipations will receive FB849 orally once a day.
Phase IIb dose-expansion part of FB849 in Combination with Pembrolizumab (Type A cancer)Phase IIb dose-expansion part of FB849 in Combination with Pembrolizumab (Type A cancer)Participations will receive FB849 orally once a day in combination with pembrolizumab.
Phase IIb dose-expansion part of FB849 in Combination with Pembrolizumab (Type B cancer)Phase IIb dose-expansion part of FB849 in Combination with Pembrolizumab (Type B cancer)Participations will receive FB849 orally once a day in combination with pembrolizumab.
Phase Ia dose-escalation part of FB849 MonotherapyPhase Ia dose-escalation part of FB849 MonotherapyParticipations will receive FB849 orally once a day.
Primary Outcome Measures
NameTimeMethod
To assess the safety and tolerability of FB849 and to identify maximum tolerated dose (MTD)/ recommended Phase II dose (RP2D) and dosing schedule of FB849 in subjects with advanced solid tumorsDLT Assessment at the end of Cycle 1(each cycle is 21 days.)

The MTD is defined to be the highest safe dose with an estimated DLT rate less than 30.

Secondary Outcome Measures
NameTimeMethod
To assess preliminary anti-tumor activity of FB849every 6 weeks (± 3 days) in the first 18 weeks, then every 12 weeks (± 7 days) thereafter until disease progression assessed up to approximately 3 years

Tumor response will be assessed by the investigator according to Response Evaluation Criteria in Solid Tumors (RECIST) version 1.1 using computed tomography (CT) or magnetic resonance imaging (MRI) of the chest, abdomen/pelvis, and additional assessments (e.g., craniocerebral imaging, bone scan) based on clinical indications.

To determine the pharmacokinetic parameters such as Peak Plasma Concentration (Cmax) of FB849Blood: Predose, 1, 2, 4, 8, 12, 24 hours postdose at C1D1 and C1D21; predose and 4, 8, and 24 hours postdose at C1D8; predose at C1D15; and predose on C2D1, C4D1, and C6D1, Urine: predose and 0-4 hour, 4-8 hour, 8-12 hour, 12-24 hour post-dose

The PK parameters should include, where appropriate, area under the concentration-time curve (AUC), maximum observed concentration (Cmax), time to maximum observed concentration (tmax), and apparent terminal elimination half-life (t1/2), apparent total body clearance (CL/F), apparent volume of distribution (Vz/F), Cmax at steady state (Css-max), minimum observed concentration at steady state (Css-min), AUC at steady state (AUCss), accumulation ratio (Rac), amount excretion (Ae), fraction excretion (Fe), renal clearance (CLR).

Trial Locations

Locations (4)

Summit Cancer Centers - Spokane Valley

🇺🇸

Spokane, Washington, United States

Mary Crowley Cancer Research Center

🇺🇸

Dallas, Texas, United States

NEXT Oncology San Antonio

🇺🇸

San Antonio, Texas, United States

Next Oncology Virginia

🇺🇸

Fairfax, Virginia, United States

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